The connection drop is accompanied by the error message "_handleLinkEvent: MT** Dropped Connection: reason=Frame received from nonassociated STA (7)" in the airport debug log.

I have invested some effort into trying to work around this problem but it seems to require either a driver fix in Mountain Lion, or a fix of the WP8 Internet Sharing code, so either Apple or Microsoft have to provide the fix. There is no workaround. I'm now ready to give up and switching my Lumia 925 for an iPhone if this is not fixed within the next month, but I'll still like to ask MS and Apple for a fix first.

So, I have filed a bug in the Apple developer network (no response yet) but I don't know where to post a Windows phone bug. Does anyone know the right place for this?

Get a Windows based PC in the future even windows on mac is not 100% and you can nowadays get good ultrabooks with high resolution screens and big battery life too.

That's not an option for me, because I love my Retina MBP Windows phone is my favorite smartphone OS though and find the Lumia range amazing - had a Lumia 800 before, which worked with no problems at all, and now upgraded to the Lumia 925, which I think is a perfect smartphone - except this damn Internet Sharing problem. I depend on this feature a lot so it's really a dealbreaker for me. And I know this wouldn't be hard to fix for either Apple or MS... if it only would be easier to get their attention. I have submitted the bug to multiple feedback channels though so fingers crossed.

That's not an option for me, because I love my Retina MBP Windows phone is my favorite smartphone OS though and find the Lumia range amazing - had a Lumia 800 before, which worked with no problems at all, and now upgraded to the Lumia 925, which I think is a perfect smartphone - except this damn Internet Sharing problem. I depend on this feature a lot so it's really a dealbreaker for me. And I know this wouldn't be hard to fix for either Apple or MS... if it only would be easier to get their attention. I have submitted the bug to multiple feedback channels though so fingers crossed.

Hello BERNHARD MUELLER, this is EXACTLY what i am facing and what i am also. I'm the purely deadly NOKIA fan and MacBOOK fan. And thus, finally having this WEIRD PROBLEM with Windows Phone. Me too still can't find any solution

Hello BERNHARD MUELLER, this is EXACTLY what i am facing and what i am also. I'm the purely deadly NOKIA fan and MacBOOK fan. And thus, finally having this WEIRD PROBLEM with Windows Phone. Me too still can't find any solution

Hi 4lvin, I tried installing OS X Mavericks GM as well as WP 8 Update 3 Developer Preview plus "Access Point" app update in the hope of fixing the issue, however none of these updates helped. I have also not received an answer to my Apple bug report. There seems to be no workaround for the issue either except a running a shell script to permanently reconnect, which is a really crappy "solution".
I don't think that there is a fix, or will be in the near future. The current options are buying a different laptop, a USB wireless dongle, or a different smartphone (personally I will go with the last option).

I managed to get this one working when I changed the screen lockdown to 5 minutes instead of 1 minute. After that I've had no problems with wifi sharing...

Thanks for sharing! I just tried your fix, but it didn't fix work for me either.
What you should do anyway is going to Settings->WiFi->Advanced and checking "Keep Wi-Fi on when the screen times out", otherwise you get disconnected after a minute. This is another common issue, but probably unrelated to the incompatibility issue.